Kay... first, the gripes. There seems to be a couple water 'quirks' tossed about the level. Most of them are good for variety's sake, but two bug me for some reason. The little "flower" of land in the center/left just looks out of place. Also, the ditch of "deep/deepest/deep" water in the bottom left looks awkward because of it's shape, really unnatural I suppose. Aside from the top left island and the water surrounding it, most of the level needs a bit more tiling thrown about.
And now for the positive, because if you end off on a good note, people will hate you less
Oddily enough, I REALLY like how the islands all roughly "jigsaw" together, if pushed closer. It's just one of those little niceties I pick up on. The actual shapes of all of the islands are really nice in my opinion, not too straight, not too random. There's a lot of improvement open to this level, especially considering you just "threw" it together; shows that if you put more time into it, it could really look great.
Rating-wise... I don't like doing this because I can't really decide a number x.x But if you're gonna force me, I'd say 6.5 - 7.
Edit: Numbers = The Devil